Scaffold



T. G. STINSON Feb. 13, 1951 SCAF'FOLD 2 Sheets-Sheet 1 Filed Feb. 6,1948 3nventor (Ittorneg T. G. STINSON Feb. 13, 1951 SCAFFOLD 2Sheets-Sheet 2 Filed Feb. 6, 1948 Zmventor name 6. 629/230 BB ZV W(Ittomeg Patented Feb. 13, 1951 UNITED STATES PATENT OFFICE SCAFFOLDTruman G. Stinson, Spokane, Wash.

Application February 6, 1948, Serial No. 6,680

1 Claim. 1

This invention relates to scaffolds audit is one object of the inventionto provide a scaffold suspended by cables coiled about drums which aremounted upon the scaffold and operated by electric motors, the motorsoperable individually or bothat the sametimeso that one end or the otherof the scaffold may be raised or lowered to level the scaffold and theleveled scaffold raised or lowered along a wall or other structure to bepainted, cleaned, or repaired.

Another object of the invention is to provide a scaffold wherein themotors are under control of a workman standing upon the scaffold andthus eliminate necessity of a ground crew to raise or lower thescaffold.

Another object of the invention is to provide a scaffold having a mainsection or platform and end sections which may be shifted longitudinallyfrom a retracted position to an extended position when lengthening ofthe scaffold is desired.

Another object of the invention is to provide a scaffold having improvedwalls for preventing tools and other articles used by workmen fromslipping off of the scaffold. I

The invention is illustrated in the accompanying drawings wherein:

Fig. 1 is a side elevation of the improved scaffold.

Fig. 2 is a view looking at one end of the scaffold.

Fig. 3 is a perspective View showing'a portion of the inner side Wall ofthe scaffold and a roller carried thereby.

Fig. 41s a top plan view of the scaffold.

Fig. 5 is a sectionalview taken through one end portion of the scaffoldalong the line 55 of Figure 4.

Fig. 6 is a perspective view of one end-portion of' the scaffold.

Fig. '7 is a wiring diagram.

This scaffold has a platform I which may be of any length and widthdesired and has side bars 2. which gradually decrease in depth towardstheir ends from a point midway the length of the platform. Floor boards3, extend transversely of the platform with their ends fitting intogrooves 4 bars midway the length of the scaffold and end portions of thesidebars carry cradles 8' which are formed of angle metal and serve asgroundengaging shoeswhen the scaffold is resting upon the ground. Theshoes are of duplicate con-' struction and each has side bars 9 and across bar ID, the cross bar being welded to inner ends of the side barsand having its end portions bent upwardly and forming arms I l which aresecured to the side bars of the platform. The side bars 9 of the cradleshave their outer end portions bent upwardly so that they arecurved. asshown in Figure 5, and from an inspection of this figure and Figure 1,it will be seen that when the scaffold is resting upon its wheels I thescaffold may be easily rolled along the ground and the upwardly curvedouter portions of the cradleswill allow ends of the scafiold to readilymove across uneven placesencountered. The scaffoldmay also be rockedupon the wheels and the ends of the scaffold tilted upwardly. whennecessary.

Walls 52 and i3 extend along sides-of the scaffold and it. should benoted that the inner wall is lower than the outer wall so thatworkmenusing the scaffold may readily reach a wall to be painted. These wallsconsist of horizontal rails l4 and I5 secured to upper ends of standardsl6 and ll rising from the side rails of the platform I and in order toprevent tools from slipping off of the outer side edge of the platformscreening [9V is secured to the rail 14 and the outer side bar of .theplatform. Bars 18 extend diagonally between ends of the railsl l and I5to support the inner. wall in a vertical position and the outer wallatan outward incline and these bracing bars also serve as rails for endwalls of the scafiold which are provided with screening 19 topreventtoolsand oher articles from dropping off ends of the scaffold.

An extension 20 has been disclosed for one end of the scaffold but itwill be understood that extensions may be provided for both ends of thescaffold. This extension has a floor 2! formed from a sheet of thicksheet metal. The sheet metal floor is formed with a longitudinally extending slot 22 and along opposite side edges of the sheet are' mountedangle metal strips 23 which fit under companion angle metal strips 24mounted along the side bars 2 of the platform I. An outer end wall 25consisting of a metal frame 26 carrying screening 21 is connected withthe floor 2! by hinges 28 and in order to support this end wall in araised position there have been provided braces 29 which extenddiagonally between side edge portions of the floor and the frame 26 andare removably secured thereto. Threaded stems or bolts extend from uppercorners of the end wall for engagement by bracing rods 3| which areremovably connected with the side walls of the scaffold. Since the endextension or auxiliary scaffold section is releasably secured by thebracing rods 29 and 3| it may be slid to extended and retractedpositions.

In order to suspend the scaffold from overhead supports there have beenprovided cables 32 having hooks 34 at their ends. These cables passthrough bushings 35' at upper ends of yokes 35 which are of invertedV-shaped formation and mounted transversely of ends of the platform I.The cables pass through the slots 22 of the floor plates 2| and throughopenings in the platform I, and under the platform the cables aretrained about pulleys 36 and extended longitudinally of the platform andwound about drums 3'! which are rotatably supported in the cradles =8.Each cable is wound about a drum at the opposite end of the platformfrom its guide pulley, and in order to rotate the drums and therebycause raising or lowering of the scaffold there have been providedmotors 38 carried by the cradles. A switch 39 is mounted at a convenientplace upon the scaffold together with a second switch 40. The movablecontact of the switch 39 is connected with one side of the battery 4| bya wire 42, the other side of the battery being connected with themovable contact of the switch 40 by a wire 43. Wires 44 and connectstationary contacts of the switch 49 with the motors and wires 46 and 41extend from the motors to the stationary contacts of the switch 39.Other wires 48 and 49 lead from the motors, the wire 48 being cut intothe wire 46 and the wire 49 being cut into the wire 41. Ordinarily themovable contact of the switch 40 is in position to connect the wire 43with both of the wires 44 and 45 and the movable contact of switch 39may then be moved to selectively close. a circuit through the motors byway of the wire 46 and the wire 41. When the circuit is closed by way ofthe wire 46 the wire is connected with one side of 4 each motor by thewires 46 and 48 and the motors will be turned in a direction to windcable upon the drums and raise the scaffold. When the other stationarycontact of the switch 39 is engaged by its movable contact theconnection with the motors is by way of the wires 4! and 49 and themotors will rotate in an opposite direction. It will thus be seen thatby proper manipulation of the switch 39 the drums may be rotated in onedirection to wind the cables thereon and raise the scaffold or in anopposite direction to unwind the cables and lower the scaffold. Bymoving the movable contact of the switch 49 into position for engagingonly one of its stationary contacts, only one motor will be operated andone end of the scaffold will be raised or lowered while its other endremains stationary. The scaffold may thus be leveled after it has beenmoved to a desired elevation or during such movement.

While the scafiold is being raised or lowered its side presented towardsa wall is liable to scrape along the wall. In order to prevent damage tothe wall there have been provided rollers 50. There have been shown twoof the spacing rollers but it will be understood that additional rollersmay be provided if so desired. These rollers are rotatably mountedbetween the arms 5! of the bearing brackets 52 which are mounted uponthe rail 15 of the inner side wall 13 and are slidable along this railto adjusted positions where they I are secured by pins 53 which arepassed through openings in the brackets and into selected ones of theopenings 54 formed vertically through the rail l5. The rollers may thusbe moved to positions in which they will bear against portions of a wallof a building between window openings and roll along the wall withoutstriking window sills as the scaffold is shifted vertically along thewall.

Having thus described the invention, what is claimed is: p

A scaffold comprising a platform having side rails and flooring carriedthereby, cradles under end portions of said platform each having sidebars and a cross bar secured thereto, end portions of the cross barbeing bent upwardly and secured to the platform and outer end portionsof the side bars being curved upwardly and secured to the platform, theside bars constituting runners, wheels under the side rails of theplatform midway the length of the scaffold and extending downwardly fromthe platform below the plane of the cradles a distance adapting thewheels to rest upon ground and mount the scaffold for vertical tiltingmovement into and out of position for alternate engagement of thecradles with the ground, drums under end portions of said platformrotatably supported in said cradles, a motor carried by each cradle forturning the drum mounted thereon, suspension cables wound about saiddrums, and cable guides of inverted V-shape extending upwardly from endportions of the platform and disposed transversely thereof and havingtheir upper ends located midway the width of the platform and formedwith openings through which the cables slidably pass.

TRUMAN G. STINSON.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 284,308 Klein Sept. 4, 1883760,239 Oursler May 17, 1904 903,478 Keil Nov. 10, 1908 929,680 LottAug. 3, 1909 984,063 Berg Feb. 14, 1911 1,000,738 Magnuson Aug. 15, 19111,113,509 Thrall Oct. 13, 1914 1,115,775 Bisboch Nov. 3, 1914 1,861,514Bottoms July 28, 1931 2,007,294 Cischke July 9, 1935 2,112,837 FisherApr. 5, 1938 2,391,172 Leland Dec. 18, 1945 2,396,127 Riblet Mar. 5,1946

